iterator

Documentation

Index

• func Reduce[T any, U any](iter Iterator[T], initial U, reducer func(U, T) U) U
• func ToChannel[T any](ctx context.Context, iter Iterator[T], buffer int) <-chan T
• func ToSlice[T any](iter Iterator[T]) []T
• type DeleteIterator
• type Iterator
  • func Filter[T any](iter Iterator[T], predicateFunc func(item T) bool) Iterator[T]
  • func FromChannel[T any](channel <-chan T) Iterator[T]
  • func FromRange[T constraints.Integer | constraints.Float](start, end, step T) Iterator[T]
  • func FromSlice[T any](slice []T) Iterator[T]
  • func Join[T any](iters ...Iterator[T]) Iterator[T]
  • func Map[T any, U any](iter Iterator[T], iteratee func(item T) U) Iterator[U]
  • func Take[T any](it Iterator[T], num int) Iterator[T]
• type PrevIterator
• type SetIterator
• type StopIterator

Functions

func Reduce

func Reduce[T any, U any](iter Iterator[T], initial U, reducer func(U, T) U) U

Reduce reduces iter to a single value using the reduction function reducer

func ToChannel

func ToChannel[T any](ctx context.Context, iter Iterator[T], buffer int) <-chan T

ToChannel create a new goroutine to pull items from the channel iterator to the returned channel.

func ToSlice

func ToSlice[T any](iter Iterator[T]) []T

Types

type DeleteIterator

type DeleteIterator[T any] interface {
	Iterator[T]

	// Delete deletes the current iterator element;
	// that is, the one returned by the last call to Next.
	// Delete should panic if called before Next or after
	// Next returns false.
	Delete()
}

DeleteIter is an Iter that implements a Delete method.

type Iterator

type Iterator[T any] interface {
	// HasNext checks if there is a next value in the iteration or not
	HasNext() bool
	// Next returns the next value in the iteration if there is one,
	// and reports whether the returned value is valid.
	// Once Next returns ok==false, the iteration is over,
	// and all subsequent calls will return ok==false.
	Next() (item T, ok bool)
}

Iterator supports iterating over a sequence of values of type `E`.

func Filter

func Filter[T any](iter Iterator[T], predicateFunc func(item T) bool) Iterator[T]

Filter creates a new iterator that returns only the items that pass specified predicate function.

func FromChannel

func FromChannel[T any](channel <-chan T) Iterator[T]

FromChannel creates a iterator which returns the numeric range between start inclusive and end exclusive by the step size. start should be less than end, step shoud be positive.

func FromRange

func FromRange[T constraints.Integer | constraints.Float](start, end, step T) Iterator[T]

FromRange creates a iterator which returns the numeric range between start inclusive and end exclusive by the step size. start should be less than end, step shoud be positive.

func FromSlice

func FromSlice[T any](slice []T) Iterator[T]

FromSlice returns an iterator over a slice of data.

func Join

func Join[T any](iters ...Iterator[T]) Iterator[T]

Join creates an iterator that join all elements of iters[0], then all elements of iters[1] and so on.

func Map

func Map[T any, U any](iter Iterator[T], iteratee func(item T) U) Iterator[U]

Map creates a new iterator which applies a function to all items of input iterator.

func Take

func Take[T any](it Iterator[T], num int) Iterator[T]

type PrevIterator

type PrevIterator[T any] interface {
	Iterator[T]

	// Prev moves the iterator to the previous position.
	// After calling Prev, Next will return the value at
	// that position in the container. For example, after
	//   it.Next() returning (v, true)
	//   it.Prev()
	// another call to it.Next will again return (v, true).
	// Calling Prev before calling Next may panic.
	// Calling Prev after Next returns false will move
	// to the last element, or, if there are no elements,
	// to the iterator's initial state.
	Prev()
}

PrevIterator is an iterator with a Prev method.

type SetIterator

type SetIterator[T any] interface {
	Iterator[T]

	// Set replaces the current iterator element with v.
	// Set should panic if called before Next or after
	// Next returns false.
	Set(v T)
}

SetIterator is an Iter that implements a Set method.

type StopIterator

type StopIterator[T any] interface {
	Iterator[T]

	// Stop indicates that the iterator will no longer be used.
	// After a call to Stop, future calls to Next may panic.
	// Stop may be called multiple times;
	// all calls after the first will have no effect.
	Stop()
}

StopIterator is an interface for stopping Iterator.